The Turkish presidency shared no further information about the closed-door meeting at the Dolmabahce Palace.
On Saturday, Stoltenberg attended the inauguration ceremony of Erdogan who took the oath of office as Türkiye's president.
Stoltenberg was among those who congratulate Erdogan after his reelection victory on May 28.
"Good call with President @RTErdogan. I congratulated him on the election. We discussed key issues for the upcoming #NATOSummit in Vilnius, continued support for #Ukraine, strengthening our deterrence & defence & finalising Sweden's accession to NATO," he said on Twitter late May.
Finland and Sweden applied for NATO membership soon after Russia launched war in Ukraine in February 2022.
Although Türkiye approved Finland's membership to NATO, it is waiting for Sweden to abide by a trilateral memorandum signed last June in Madrid to address Ankara's security concerns.
Sweden passed an anti-terror law last November, hoping that Ankara would approve Stockholm's bid to join NATO. The new law, effective as of June 1, allows authorities to prosecute individuals who support terrorist groups.
Several foreign ministers hope that Türkiye would approve Sweden's bid ahead of a NATO summit which will be held in Lithuania's capital Vilnius on July 11-12.